PNGTreesKey – Pinus merkusii Jungh & de Vriese.


Barry Conn (NSW) & Kipiro Damas (LAE).
Guide to trees of Papua New Guinea
Copyright held by the authors, National Herbarium of New South Wales, and Papua New Guinea National Herbarium

Pinus merkusii Jungh & de Vriese.

in de Vriese, Plantae Novae et Minus Cognitae Indiae Batavae Orientalis 5 (1845) Fig. 2.

Family: Pinaceae

Timber Group: Softwood or Plantation species Tradename: Tenaserrim Pine

Field Characters: Large canopy tree (20-35 m high - usually smaller in PNG); Bole cylindrical (c. 25 cm diam.); crooked or straight (branching from near base); buttresses buttresses absent; spines spines absent; aerial roots aerial roots absent; stilt roots stilt roots absent; Bark grey or rarely brown, rough (deeply furrowed), fissured or furrowed cork (forming a reticulate pattern); Subrhytidome (under-bark) dark brown; less than 25 mm thick (12 mm thick), 12.0 (c.); bark blaze with two layers (outer layer of dead cork); strongly aromatic; resinous/linament-like or pine-like; outer blaze red or brown, with stripes (layers of cork), corky; inner blaze white, markings absent, fibrous; bark exudate (sap) present, yellow or colourless, not readily flowing (spotty) (flowing after some time), colour not changing on exposure to air (except when hardening then turning white/milky to pale yellow), sticky; terminal buds not enclosed by leaves.

Indumentum: Complex hairs absent; stinging hairs absent; mature twig indumentum (hairs) absent.

Leaves: Leaves clustered at end of branches (young shoots usually with 2 or more whorls of branches), whorled (with more than two leaves at one node of a branchlet), 2, simple (a leaf composed of a single blade) (with persistent basal sheath 1-2 cm long); petiole absent; leaves equally broad throughout much of length (linear), 20.0-38.0 cm, 0.2 cm; symmetric, finely crenate, not dissected or lobed, obtuse, venation parallel-veined, secondary veins closed, not prominent, but visible, intramarginal veins absent (resin canals in median position - view in cross-section); leaves lower surface green (glossy) or yellow (greenish (convex), upper surface green (glossy) or yellow (greenish (upper, hence inner surface 2-sided; outer surface concave), indumentum (hairs) absent; absent; domatia absent; stipules absent.

Flowers: Inflorescence terminal or axillary, flowers on an unbranched axis, flowers arranged in a cone (strobilus) (male flowers in narrowly cylindrical strobili, strobili in clusters around base of young shoots); flowers unisexual, unisexual with male and female flowers on the same plant, not stalked, flowers with one plane of symmetry; perianth absent; stamens 1, absent, free of each other; ovary superior, carpels separate (when more than one), locules 2; styles absent.

Fruits: Infrutescence arranged on unbranched axis, arrangement of fruits present (narrowly cylindrical, often curved, either occurring singly or in pairs), cone 60.0-90.0 mm, 30.0 (c.) mm, green or brown; seeds 100 (2 per scale), to about 5 mm long, winged (well-developed), narrow (longer than wide).

Distribution: Morobe (Plantation species).

Pinus merkusii
Botanical records
in PNGplants database

Map details